The Engineering Of Recirculated Semi-Aerobic Landfill For A Town,Tianshui City

At present,there are not have a perfect disposal facilities of garbage for the town Guanzi and Xikou in Qinzhou district,Tianshui City.The garbage was cluttered and there are poor Environmental Health conditions.This paper combined the experience from the design of landfill in domestic and foreign,standing on the background of actual engineering project design,through the site survey and access to relevant information.The semi-aerobic landfill and leachate recirculation which come from the Sanitary landfill were selected in this paper at the end.The calculations and blueprint for main project have been completed at the same time.The proposed landfill site is located at the Panshi village where the Damazi ditch are existed,lying in south of the town government shut the road about 5.0km.The reservoir utilized the middle to upstream of ditch and length is 320m approximately.Service area of the landfill include the town Guanzi and Xikou,moreover,the administrative villages under the jurisdiction of two towns and villages.The 316 national road and Township road can each the reservoir of landfill.The average quantity of waste will be 68t/d after the completion of Landfill,the total design capacity is 540,000 m~3 and the effective capacity of 470 000 m~3.The project has completed a feasibility study Currently.Four aspects of the corresponding engineering measures have been given in this paper for“The realization of semi-aerobic environment in landfill,the leveling of slope which are High and Precipitous,the diversion of groundwater and the circulation of Leachate”.It achieved a halfpipe stream by increasing the diameter of main pipeline,realizing a“Three-dimensional guide row”by combining the shafts and Horizontal pipe at the same time.That promoted the circulation of gas which exist in inside and outside of landfill.In addition,according to the characteristics of terrain and the slopes on both sides of reservoir,it reduces the difficulty of construction by cut dig the left side of slopes,the bottom of the reservoir was extended simultaneously.It choose a“grass-mud mixture layer”to instead the traditional protective layer which under the impermeable membrane,it ensured the safety when impermeable membrane are lying.The diversion of groundwater use a method that is“discharge at first and diversion keep up”,lying the diversion layer and discharge blind ditch above the bottom of reservoir after the spring from upstream and downstream have been dischaged.And it can discharge smoothly after taking front measure.It should ensure the moisture content of garbage always lower than specific retention when the leachate was been rechaged.This paper design the discharge recirculation systems stand on four basic principles,ensuring the safety and stable of Leachate recirculation.The recirculated semi-aerobic landfill have a small number of projects in our country,lacking of a relevant experience.The design ideas in this paper for“Valley type landfill”can provide a reference for the design of Semi-aerobic landfill and Leachate recirculation in China.This design is also available as a reference scheme for the initial design and construction for Guanzi Solid waste sanitary landfill.